和静县哈勒哈特菱镁矿地质特征与找矿方向

ORE-FORMING CONDITIONS AND GENESIS OF THE HALEHATE MAGNESITE IN HEJING,XINJIANG

新疆和静县哈勒哈特菱镁矿，产于南天山中泥盆统萨阿尔明组下段第五岩性层中，该矿床由32个矿体组成，主要赋矿岩性为厚层白云岩夹菱镁矿透镜体、矿化白云岩及少量生物碎屑灰岩．矿石矿物为菱镁矿，脉石矿物主要为白云石．哈勒哈特菱镁矿中MgO含量为41．82％-45．87％，CaO含量为1．23％～5．54％，Si02含量为0．24％～0．85％，矿石主要为半自形粗晶结构，块状构造．矿床成因类型是与区域变质作用有关的热液矿床．经研究对比发现，可利用矿区地层、构造、地貌和矿物标志等作为矿区和区域找矿标志．

Halehate magnesite of Hejing county in Xinjiang lies in South Tianshan, produced in the fifth paragraph of lower Saaerming formation in Middle Devonian. The deposit has 32 ore bodies with different size and the distribution and occurrence of the deposit is significantly controUed by tectonic fracture zones. The main Ore-bearing rock is thick dolomite with magnesite lenses,mineralized dolomite and a small amount of biological limestone.Magnesite is ore mineral and dolomite is main gangue mineral. The MgO,CaO and SiO2 content of Halehate magnesite in generally is 41.82-45.87%, 1.23-5.54% and 0.24-0.85% respectively.Ores mainly are subhedral coarse grain structure,block structure.Genetic type of deposit should be low-temperature hydrothermal deposits related to regional metamorphism.Comparative study found that stratigraphy, tectonics,geomorphology and minerals can be used for mining and regional prospecting.